The invention is concerned with local bone regeneration. More specifically, the invention relates to the use of locally-applied vacuum to stimulate osteoblastic activity in the area treated.
Osteogenesis, the growth of new bone, is a part of the normal healing process, and involves recruiting and activating osteoblast cells in bone. This can be a slow process, particularly in the elderly and after severe trauma to the bone and after disease. The ability to accelerate osteogenesis would speed the healing process after trauma and after orthopedic and dental procedures. Methods to accelerate the process, particularly in local areas of bone, have been a holy grail for scientists for many years. The holy grail has not yet been found.
Current techniques of bone regeneration include: traditional methods such as distraction osteogenesis in which bone is pulled in an appropriate direction to stimulate growth, and bone grafting; and, experimental techniques that include use of drugs such as OP-1 that stimulate osteoblasts, implanting biomaterials laced with molecular signals designed to trigger the body""s own repair mechanism, injecting bone marrow stem cells into the affected areas, and, transfusing cells that carry genes that code for bone-repair proteins. None of these methods are yet totally satisfactory, for a host of reasons. For a review of this subject see: Service, Science, 289:1498 (2000).
Distraction osteogenesis requires a bulky device and requires a very long period before positive results are seen. Bone grafting is limited by the quantity and quality of the patient""s bone available for grafting. Biocompatible polymeric matrices without or with natural or recombinant bone morphogenic proteins suffer from a need for very large and very expensive quantities of these signal proteins. The gene therapy procedure suffers from the general problems of gene therapy in general. The use of the stem cell approach is greatly limited by the scarcity and expense of such cells; for example, in 50-year olds, there is only one stem cell in 400,000 bone marrow cells (see Service, 2000, above.
Clearly, there is an acute need for a safe, simple, rapid, inexpensive and efficient method for producing osteogenesis in selected areas of bone. Such a method has been discovered, and is described below.
A method of producing bone regeneration (osteogenesis) in a local area of a bone in a subject requiring same, comprising the step of applying to the local area of the bone a vacuum (subatmospheric pressure) for an effective length of time.
In one embodiment, the local area of the bone is sealed from the atmosphere with a flexible, sterilizable suction cup device of a dimension and curvature suitable to enclose and fit tightly over the desired local area of the bone. The cup is then evacuated by means of an entry port in the base of the cup linked to a vacuum pump, and the cup entry port is then sealed. The sealed suction cup is kept in place for for an appropriate length of time.
In still another embodiment, suitable suction cup devices are provided.